Bootable 64-bit RPi3 Gentoo image (OpenRC/Xfce/VC4) UPDATED

Sakaki · Guru Joined: 21 May 2014 Posts: 409

If you haven't done so already, do try commenting out the "dtoverlay=vc4-fkms-v3d" line in /boot/config.txt. Otherwise nothing will show until the vc4 kernel module is loaded, and that requires a correct root mount (of your USB device) etc.
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sakaki

NeddySeagoon · Posted: Mon Sep 04, 2017 3:35 pm Post subject:

Having poked about with a multimeter and a 'scope, the 3.3v regulation on the Pi is pretty good.
Its less than 100mv pk-pk ripple but it does need the headroom for the 5v to 3.3v regulator.

As long as the red LED stays lit you should be good.

The 5v PSU I have shows ripple of 400mv pk-pk and 300mv droop when the Pi is working hard.
Other than the Pi itself, the 5v only powers a wireless USB connected Logitech MK300 mouse and keyboard receiver.

Users with a USB memory stick can draw 500mA for that alone.
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NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

dr_wulsen · Posted: Mon Sep 04, 2017 4:12 pm Post subject:

@zucca: have you appended something like root=/dev/sda rootwait to your cmdline.txt?

@roylongbottom: higher than 85 is not possjble on the Pi3, even if you set the temp limit in config.txt higher, it's hardcoded to 85. at that point, it will throttle the cpu to 600MHz, regardless of governor and settings.

For stresstests, compiling etc. I have some piece of origami that is a paper tunnel taped to the pi case with an 80mm fan on top

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There's no stupid questions, only stupid answers.

Zucca · Posted: Mon Sep 04, 2017 5:57 pm Post subject:

NeddySeagoon · Posted: Mon Sep 04, 2017 6:04 pm Post subject:

Zucca,

Show us

Zucca · Posted: Mon Sep 04, 2017 6:16 pm Post subject:

NeddySeagoon · Posted: Mon Sep 04, 2017 6:35 pm Post subject:

Zucca,

Zucca · Posted: Mon Sep 04, 2017 6:39 pm Post subject:

Neddy,

All files are straight from Sakaki's image (via github).

Should I add something like kernel=kernel8.img to config.txt?
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..: Zucca :..

Sakaki · Guru Joined: 21 May 2014 Posts: 409

It should be fine as is. You can add

NeddySeagoon · Posted: Mon Sep 04, 2017 7:03 pm Post subject:

Zucca,

Sakakis image works. :)

I don't think its mounting root.

Did you make a new partition table on the SD card where /boot is?
bootcode.bin checks for the bootable flag and the partition type of boot in the partition table.

There is a minor gotcha with mkfs.vfat too. You must tell it you want FAT32 or it guesses the FAT type from the volume size and may not do what you want.
It matters to the Pi.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

Zucca · Posted: Tue Sep 05, 2017 5:46 am Post subject:

Hi folks.

The "vanilla" image works.
The partition has bootable flag set. And I have forced the boot partition to be FAT32 specifically. That should be ok, since the bootloader creates the rainbowsquare and it's being loaded from the FAT partittion?

EDIT: I looked at the SDcard that has the "vanilla" image and there the FAT32 boot partition does NOT have bootable flag set. I tried with that flag unset on the SDcard that I'm trying to get boot, but no any visible effect.
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..: Zucca :..

NeddySeagoon · Posted: Tue Sep 05, 2017 9:33 am Post subject:

Zucca,

Rebuild the kernel with Simple Framebuffer added. This is the one I use.
You will get a console provided the kernel loads.

You don't care about installing the kernel modules until root mounts but console messages might be useful.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

Sakaki · Guru Joined: 21 May 2014 Posts: 409

Zucca,

you mentioned you were able to boot the vanilla image successfully, on a spare microSD card.

One quick diagnostic therefore would be to boot this (vanilla) image again, insert your root USB stick, ensure that you can mount it and read the contents OK, then edit the (vanilla) image's /boot/cmdline.txt (setting root=/dev/sda1 rootdelay=5 or similar), optionally edit /boot/config.txt, and then reboot (with your USB root stick still inserted).

This should eliminate any issues about the other microSD card's integrity, correct formatting of the boot partition etc.

If that fails then compile your own kernel, per Neddy's suggestion, and try that.
_________________
Regards,

sakaki

Zucca · Posted: Tue Sep 05, 2017 11:19 am Post subject:

Mates,

Some success.
The Pi actually booted using the "vanilla" SDcard with modified cmdline.txt.
However X isn't started automatically and I'm left with getty login. It says the hostname is "none" (unset).

My guess why the other card didn't work is becuase Pi is very picky about the formatting of the card. I tried to mimic every part of the "vanilla" image's partition... dos partition table, FAT32 etc... Only real difference was the size. I had set it to 2gig (spare space for alternative kernels and initrds).

Anyway. At this point I just need to be able to set the password to demouser and rest I can do via ssh.

EDIT: Oh and what comes to the power delivery problems, they seem to be gone. I believe I found a reason, an external one, for it. I had a Li-ion/NiMH battery charger in the same outlet group. One evening I removed the charged batteries from it and at that point I could hear coil whining from it. After I unplugged the battery charger all the problems powering the Pi vanished. Keeping my fingers crossed now... If that was really the case, I'll open that charger and see how (badly) the switching circuit is made. Luckily I have another charger that is better in every way so I can throw that bad charger to trash. It wasn't any cheapo eBay charger but a Nitecore charger bought from local store.
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..: Zucca :..

Sakaki · Guru Joined: 21 May 2014 Posts: 409

Zucca,
good news ^-^
Obviously now all is basically running you can check /var/log/rc.log, /var/log/messages etc to see if everything else is coming up OK.
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Regards,

sakaki

Zucca · Posted: Tue Sep 05, 2017 1:50 pm Post subject:

Sakaki · Guru Joined: 21 May 2014 Posts: 409

Zucca,
Looks like your system is not bringing up OpenRC properly. Are you sure /etc/fstab is correct on the USB (ie has specified / on /dev/sda1 or whatever)? Also are you sure you preserved all symbolic links, ownership, permissions etc. when copying the root files from the image?
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Regards,

sakaki

Zucca · Posted: Tue Sep 05, 2017 2:28 pm Post subject:

Sakaki · Guru Joined: 21 May 2014 Posts: 409

Any OpenRC errors showing on the console at boot?
Ps you can just copy /etc/passwd and /etc/shadow from the root partition on the vanilla image onto the USB stick, to clone the passwords.
_________________
Regards,

sakaki

Zucca · Posted: Tue Sep 05, 2017 3:10 pm Post subject:

Zucca · Posted: Tue Sep 05, 2017 4:17 pm Post subject:

PEBCAK.

I had still LABEL=PI_BOOT on my fstab while I was using the "vanilla" SD to boot. For some reason OpenRC doesn't start any services if mounting /boot fails.

I'll try to sort out the booting problem later, but at least now I have a Pi that boots and mounts its root from usb stick.

Thanks Sakaki, Neddy and dr_wulsen!!!
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..: Zucca :..

NeddySeagoon · Posted: Tue Sep 05, 2017 7:48 pm Post subject:

Zucca,

Openrc went through a period of requiring the nofail option in /etc/fstab if failing to mount a filesystem didn't matter.
Failing to mount a filesystem without that option caused booting to fail.

This made a lot of people with remote system that failed to boot, very unhappy. The logic was changed in some later version of openrc to be backwards compatible with the old expected behaviour.

I don't know if you have an affected openrc version or not.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

Zucca · Posted: Tue Sep 05, 2017 7:54 pm Post subject:

Neddy, I see. I guess I then add nofail options to fstab...

Another thing. How can I cache BINHOST "Packages" file locally? It would be neat if it only got downloaded when --sync:ing.
Every time I run any emerge command it downloads some megabytes of data from https://isshoni.org/pi64/Packages.
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..: Zucca :..

NeddySeagoon · Posted: Tue Sep 05, 2017 9:01 pm Post subject:

Zucca,

I don't think that would be useful. The content of the BINHOST can change at any time.
Not just when you sync.

If you know you don't want to use the BINHOST, put

Zucca · Posted: Wed Sep 06, 2017 8:10 am Post subject:

Ok. Thanks. I think I'll create an alias for binhost merging.
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..: Zucca :..